I don’t think it’s mentioned in the linked Brigandi article (and admittedly I did not read the entire thing.) But you see this secretarial or “clubhouse” style Ruth on many Yankees Team-signed Balls from the 1920s. It is quite common, and once you’ve seen it, it's unmistakeable.
The best form of education might be to search major auction archives (Heritage, Lelands, REA, etc.) Using key words “secretarial”, “clubhouse”, and “Ruth” should yield quite a few examples. The most glaring tell-tale signs are the exaggerated slant, the quote marks, and the oversized looping nature of the letter “R” in Ruth. Also, these clubhouse versions were typically done in a "lighter hand" (with less pen pressure).
Here’s a quick example from 1928 that I found in a previous REA auction, which exhibits the same clubhouse attributes... and most likely was done in the same hand as the one posted above...
https://www.robertedwardauctions.com...d-ball-gehrig/